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Aqueous reductive amination using a dendritic metal catalyst in a dialysis bag
Jorgen S Willemsen1, Jan C M van Hest, Floris P J T Rutjes
1Radboud University Nijmegen, Institute for Molecules and Materials, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands.
Beilstein Journal of Organic Chemistry
|June 15, 2013
Summary
Water-soluble dendritic iridium catalysts were synthesized and used in aqueous reductive amination. The encapsulated catalysts effectively drove complex reactions to completion, demonstrating their suitability for such applications.
Area of Science:
- * Coordination Chemistry
- * Catalysis
- * Supramolecular Chemistry
Background:
- * Development of water-soluble catalysts is crucial for green chemistry applications.
- * Dendrimers offer unique properties for catalyst immobilization and enhanced reactivity.
- * Reductive amination is a key transformation in organic synthesis.
Purpose of the Study:
- * To synthesize water-soluble dendritic iridium catalysts.
- * To investigate the application of these catalysts in aqueous reductive amination within a compartmentalized system.
- * To evaluate the efficiency and scope of the encapsulated dendritic catalyst.
Main Methods:
- * Synthesis of iridium catalysts attached to DAB-Am dendrimers using an asymmetric bipyridine ligand.
- * Application of the dendritic catalysts in the aqueous reductive amination of valine.
- * Encapsulation of the catalyst within a dialysis bag to create a compartmentalized reaction environment.
Main Results:
- * Successful synthesis of water-soluble dendritic iridium catalysts.
- * Comparable reaction conversions achieved for encapsulated catalysts versus non-encapsulated counterparts.
- * Slightly extended reaction times observed for the compartmentalized system.
Conclusions:
- * The developed dendritic iridium catalyst system is effective in water.
- * Catalyst encapsulation within a dialysis bag allows for successful driving of complex reaction mixtures.
- * The compartmentalized system demonstrates suitability for reactions involving multiple equilibrium steps.
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